Australia’s estimated resident population was 21.9 million at June 2009 (based on 2006 Census data). As the population continues to increase, both in numbers and in affluence, there is more pressure on the environment.

This section looks at a number of trends which are drivers of environmental change, including population growth, population structure and distribution, gross domestic product (GDP) and changes in people’s expenditure.

Populationgrowth occurs as a result of natural increase (defined as the number of births less the number of deaths) and migration patterns. Trends in natural increase and migration patterns have resulted in uneven population growth and distribution across Australian states and territories. Despite the large land area of Australia, the majority of the population is located in two widely-separated coastal regions. Where people live has environmental implications for air quality, and land and water degradation. Other consequences of population growth, such as increased waste generation and energy use, can also have negative environmental impacts.

Economic growth (as measured by GDP) is a key determinant of employment and, therefore, of the economic wellbeing of households. However, economic activity often has associated environmental costs. For example, economic activity, especially among the more energy-intensive industries, is associated with the creation of greenhouse gas emissions. Another example of environmental costs associated with economic activity is in the agriculture industry, where the use of irrigation can reduce water flows and quality in rivers, thereby affecting riverine flora and fauna and human health. On the other hand, higher incomes can provide resources to address environmental issues. There is a debate about how to balance economic progress, often measured by gross domestic product (GDP), against the need to maintain resources for future generations – getting this balance right is often referred to as environmental sustainability. Depletion-adjusted GDP is a way of incorporating the damage to environmental assets that is associated with economic activity.